Carlisle sewage whizzed into sludge cake

The 36 revs-per-second machine can whizz the water out of treated sewage faster than a washing machine spin-cycle, making it 25% more efficient than the old pressing method.

The sludge cake is destined for local farms to be used as soil conditioner.

United Utilities process controller, Robert Corry, said: “Recycling is nothing new to us. We’ve been doing it for decades. But while the basic process of bacterial breakdown hasn’t changed, new technology gives it a real boost.”

Work on the new machine has finished and once testing and trials are completed later this month it will be in full production five days a week.

The new centrifuge is the latest in a series of improvements to the Willowholme site since 2009 totalling more than £26m of investment. Others include a new inlet screen, a unit to remove phosphates and a pumping station to help prevent flooding.

Work has also started on the next improvement; a £1.4 million investment in new bridge scrapers and tracks, which scrape the sludge from the sides of the primary settlement tanks.

The improvements are part of a £3.6 billion scheme by United Utilities to improve water quality and the environment across the North West by 2015.

Alison Brown